tire

Abstract

We provide tires with excellent durability. [Solution] A tire comprising a band and a tire member made of a rubber composition containing recycled carbon black, wherein the band includes at least one band ply in which a plurality of band cords made of polyethylene terephthalate fibers are arranged, and when the thickness of the tire member is A (mm), the total amount of carbon black in the rubber composition, including recycled carbon black, in the rubber composition is B (parts by mass) per 100 parts by mass of rubber component in the rubber composition, the number of band cords driven in per 50 mm band ply width in a cross section perpendicular to the longitudinal direction of the band cords (cords / 50 mm), and the diameter of the band cords is D, then a tire in which A to D satisfy the following formula (1). (1) 0.07

Description

Technical Field

[0001] The present invention relates to a tire.

Background Art

[0002] A band includes a band cord and is a tire member that plays a role in suppressing the outer diameter growth of a tire. For example, Patent Document 1 describes a tire provided with a band that achieves both noise performance and low fuel consumption performance.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

Means for Solving the Problems

[0005] [[ID=4^]]The present invention relates to the following tire. A tire including a band and a tire member composed of a rubber composition containing recycled carbon black, where the band includes at least one band ply in which a plurality of band cords made of polyethylene terephthalate fibers are arranged, where the thickness (mm) of the tire member is A, where the total amount (parts by mass) of carbon black including recycled carbon black in the rubber composition is B with respect to 100 parts by mass of the rubber component in the rubber composition, where the number of driven-in band cords per 50 mm of the band ply width (number / 50 mm) in a cross section orthogonal to the longitudinal direction of the band cord is C, <00001^9>when the diameter (mm) of the band cord is D, Tires A through D satisfy the following equation (1). (1) 0.07 <D×C / (B×A)<0.60 [Effects of the Invention]

[0006] According to the present invention, it is possible to provide a tire with improved durability.

[0007] While not intended to be constrained by theory, the following mechanisms are considered to improve durability in this invention: (A) Polyethylene terephthalate is a highly rigid cord material, and when used in band cords, it allows for a thinner band topping rubber. (B) Recycled carbon black absorbs more moisture than ordinary carbon black, thus promoting heat dissipation in the rubber composition. (C) A tire in which the thickness of the tire component containing recycled carbon black, the total amount of carbon black contained in the rubber composition constituting the tire component, the number of band cords inserted, and the diameter of the band cords are balanced to satisfy equation (1) is considered to be a tire with a thin tire component and a low carbon black content, and is thought to be able to suppress heat accumulation and heat generation in the tire. It is thought that the cooperation of (A) to (C) makes it less likely for the tire to become hot, and the durability of the tire is improved overall. [Brief explanation of the drawing]

[0008] [Figure 1] This is a planar cross-sectional view of a tire according to one embodiment of the present invention, including the tire rotation axis. [Modes for carrying out the invention]

[0009] The following describes a tire that is one embodiment of the present invention. The tire of this embodiment is a tire comprising a band and a tire member made of a rubber composition containing recycled carbon black, wherein the band includes at least one band ply on which a plurality of band cords made of polyethylene terephthalate fibers are arranged, and when the thickness of the tire member is A (mm), the total amount of carbon black in the rubber composition, including recycled carbon black, in the rubber composition is B (parts by mass) per 100 parts by mass of rubber component in the rubber composition, the number of band cords driven in per 50 mm band ply width in a cross section perpendicular to the longitudinal direction of the band cords (cords / 50 mm), and the diameter of the band cords is D, then A to D satisfy the following formula (1). (1) 0.07 <D×C / (B×A)<0.60

[0010] Equation (1) is, 0.16 <D×C / (B×A)<0.55 It is preferable that it be so.

[0011] Tires that meet equation (1) under more stringent conditions are considered to have even greater durability.

[0012] The number of band cords inserted is preferably 40 to 80 per 50 mm of ply width of the band ply.

[0013] As the rigidity of the band increases and the amount of band topping rubber is reduced, the weight of the components is reduced and heat dissipation is promoted, which is expected to further improve durability.

[0014] The diameter of the band cord is preferably less than 1.2 mm.

[0015] The large specific surface area of ​​the band cord increases the contact area between the band cord and the band topping rubber, which is expected to increase the rigidity of the band and further improve its durability.

[0016] The total amount B of carbon black is preferably 25 parts by mass or more per 100 parts by mass of rubber component.

[0017] It is believed that the durability of the rubber composition is further improved by having a predetermined total carbon black content.

[0018] The fineness of the aforementioned band cord is preferably 1000 dtex or more.

[0019] It is believed that using band cords with a fineness of a specified degree or higher will improve the durability of the tires.

[0020] The tire component is preferably at least one selected from the clinch apex, base tread, inner liner, sidewall, and insulation.

[0021] It is believed that improving the durability of these components will also improve the durability of the tires.

[0022] The tire component is at least one selected from the clinch apex, base tread, and sidewall, and the rubber composition preferably contains 40% to 80% by mass of isoprene-based rubber in 100% by mass of the rubber component.

[0023] It is believed that a higher proportion of high molecular weight polymer components will further improve tire durability.

[0024] The tire component is at least one selected from the clinch apex, base tread, and sidewall, and the rubber composition preferably contains 20% to 60% by mass of butadiene rubber in 100% by mass of the rubber component.

[0025] The increased flexibility of the rubber composition is expected to further improve the durability of the tires.

[0026] The tire component is an inner liner, and the rubber composition preferably contains more than 80% by mass of butyl rubber out of 100% by mass of rubber components.

[0027] Improved air permeability, reduced tire deformation, and decreased heat generation are expected to further enhance tire durability.

[0028] It is preferable that the number of band chords placed in the outer region of the band is greater than the number of band chords placed in the central region of the band.

[0029] By arranging the band cords in this way, the overall durability of the tire is expected to improve.

[0030] It is preferable that the stiffness of the band cords located in the outer region of the band is higher than that of the band cords located in the central region.

[0031] By arranging the band cords in this way, the overall durability of the tire is expected to improve.

[0032] The maximum load capacity of the aforementioned tire W L Ratio of tire weight G (kg) to (kg) (G / W L ) is preferably 0.0135 or less.

[0033] Golden Week L Tires that meet the specified value or below are considered to be lightweight relative to their size, and their durability is thought to be improved.

[0034] The band cord is preferably made of recycled polyethylene terephthalate fibers.

[0035] In this specification, the upper and lower numerical limits related to "greater than or equal to" and "less than or equal to" in the description of numerical ranges are numbers that can be arbitrarily combined, and in addition, the numerical values ​​in the examples can also be combined with these upper and lower limits. Furthermore, in this specification, a numerical range shown as including both ends of the range is understood to simultaneously include a numerical range that does not include either of the two ends of the range, and even a numerical range that does not include either of the two ends of the range, as long as this does not contradict the spirit of the present invention.

[0036] [Definition] "Tread" refers to a component that includes the part that forms the tread surface of a tire. In the radial cross-section of the tire, if the tire has components that reinforce and form the tire skeleton, such as a reinforcing layer and carcass, on the radially inner side of the tire, the tread is a component that is positioned radially outward from these components.

[0037] "Standard condition" refers to a state of no load where the tire is mounted on a standard rim and filled with air at the standard internal pressure. Unless otherwise specified, tires in the standard condition should be used.

[0038] Unless otherwise specified, the "dimensions of each part of the tire" refer to values ​​that are determined in the normal state for those visible on the outer surface of the tire, while those located inside the tire or on the cut surface of the tire refer to values ​​that are determined, for example, by cutting the tire in a plane including the tire's axis of rotation and holding the cut tire piece within the rim width of the normal rim.

[0039] A "standard rim" refers to the rim specified for each tire within the standards system that the tire is based on. For example, for JATMA (Japan Automobile Tire Manufacturers Association), it refers to the standard rim for the applicable size listed in the "JATMA YEAR BOOK," for ETRTO (The European Tyre and Rim Technical Organisation), it refers to the "Measuring Rim" listed in the "STANDARDS MANUAL," and for TRA (The Tire and Rim Association, Inc.), it refers to the "Design Rim" listed in the "YEAR BOOK." Refer to JATMA, ETRTO, and TRA in that order, and if an applicable size is available at the time of reference, follow that standard. In the case of a tire not specified in the above standards, it refers to the narrowest rim width among the smallest diameter rims that can be mounted on that tire and that can maintain internal pressure (i.e., do not cause air leakage between the rim and tire).

[0040] "Regular internal pressure" refers to the air pressure specified for each tire in the standards system, including the standard on which the tire is based. For example, for JATMA it refers to "maximum air pressure," for ETRTO it refers to "INFLATION PRESSURE," and for TRA it refers to the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES." As with regular rims, refer to JATMA, ETRTO, and TRA in that order, and if there is an applicable size at the time of reference, follow that standard. In the case of tires not specified in the above standards, it refers to the regular internal pressure (but at least 250kPa) of another tire size (but specified in the standard) that is listed with the aforementioned regular rim as the standard rim. If multiple regular internal pressures of 250kPa or higher are listed, refer to the lowest value among them.

[0041] "Regular load (kg)" refers to the load specified for each tire in the standard system that the tire is based on. For example, for JATMA it is "Maximum Load Capacity," for ETRTO it is "LOAD CAPACITY," and for TRA it is the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES." As with regular rims and regular in-tire pressure, refer to JATMA, ETRTO, and TRA in that order, and if an applicable size is available at the time of reference, follow that standard. For tires not specified in the above standards, the maximum load capacity (kg) is calculated separately. L This is considered the normal load.

[0042] "Maximum load capacity W L The weight (kg) is calculated using the following formula: "V" is the virtual volume of the tire (mm²). 3 ), "Dt" is the outer diameter of the tire in the normal state (mm), "Ht" is the height of the tire's cross-section in the radial direction in a plane containing the tire's axis of rotation (mm), and "Wt" is the width of the tire's cross-section in the normal state (mm). Ht can be calculated by (Dt-R) / 2, where R is the rim diameter of the tire. Wt is the value obtained by removing any patterns or letters on the tire's sidewall. Note that the maximum load capacity is synonymous with the normal load mentioned above.

[0043]

number

[0044] "Tire outer diameter Dt" refers to the outer diameter of the tire in its normal state.

[0045] "Tire section width Wt" refers to the maximum width between the outer surfaces of the sidewalls in a normal state (excluding patterns or letters on the tire sidewall if any).

[0046] "Tire section height Ht" refers to the height in the radial direction of the tire's cross-section, defined by the plane containing the tire's axis of rotation. When the tire's rim diameter is R, it corresponds to half the difference between the tire's outer diameter Dt and its rim diameter R. In other words, the section height Ht can be calculated using (Dt-R) / 2.

[0047] "Tire weight" refers to the weight of the tire alone, excluding the weight of the rim. However, if the tire contains components such as sponge or sealant, or sensor components within its internal cavity, the weight includes these components.

[0048] "Recycled carbon black" refers to carbon black obtained by crushing used tires and other products containing carbon black, and then calcining the crushed material. According to the thermogravimetric method compliant with JIS K 6226-2:2003, when oxidative combustion occurs in air, the proportion of the unburned ash component (ash content) is 13% by mass or more. In other words, the proportion of the mass (carbon content) lost due to oxidative combustion in recycled carbon black is 87% by mass or less. Recycled carbon black is sometimes denoted as rCB. In this specification, carbon black that is not recycled is sometimes referred to as "ordinary carbon black" to distinguish between the two.

[0049] "Tire component thickness" refers to the maximum thickness (mm) of the tire component in the cross-section of the tire along a plane containing the tire's rotation axis. This maximum thickness is measured by creating a tire piece by cutting the tire along a plane containing the tire's rotation axis, and maintaining the distance between the beads of the tire piece at the normal rim width. This thickness is the average of the thicknesses measured at five points where the tire is rotated 72 degrees at a time.

[0050] In the cross-section of the tire, if the thickness of the tire member is substantially uniform, the thickness at a predetermined location shall be considered the thickness of the tire member. That is, (1) for a member whose thickness in the radial direction of the tire can be recognized on the tire centerline, that thickness shall be considered the thickness of the member, and (2) for a tire member whose thickness in (1) cannot be recognized, for a member whose thickness at the position of the tire's maximum width in the tire rotation axis direction can be recognized, that thickness shall be considered the thickness of the member. Examples of tire members in (1) include the base tread, inner liner, insulation, etc. Examples of tire members in (2) include the sidewall, etc.

[0051] On the other hand, if the thickness of the tire component changes in the cross-section of the tire, the thickness is determined by taking into account the usual method for determining the thickness of that tire component. Examples of such tire components include clinch apex.

[0052] "Base tread thickness" refers to the thickness in the radial direction of the tire along the tire centerline in a cross-section of the tire that includes the tire's axis of rotation. This corresponds to T5 in Figure 1.

[0053] "Inner liner thickness" refers to the thickness in the radial direction of the tire along the tire centerline in a cross-section of the tire that includes the tire's axis of rotation. This corresponds to T4 in Figure 1.

[0054] "Sidewall thickness" refers to the thickness at the point of maximum tire width in the direction of the tire's rotation axis, in a cross-section of the tire that includes the tire's rotation axis. This corresponds to T3 in Figure 1.

[0055] "Clinch apex thickness" is the thickness measured along the normal to the main body of the carcass that passes through the point where the sidewall and the clinch apex contact on the outer surface of the tire. This corresponds to T2 in Figure 1.

[0056] The "thickness of the inflation" is the thickness in the tire radial direction on the tire center line in the cross section of the tire by a plane including the tire rotation axis. T7 in FIG. 1 corresponds to this.

[0057] "Fineness" (tex) refers to the weight (g) per 1000 m of the organic fiber cord. dtex is a unit representing one-tenth of tex and corresponds to the weight (g) per 10 km of the organic fiber cord. In this specification, the fineness of the band cord is measured in accordance with JIS L1017. Also, when the band cord is composed of two or more single filaments twisted together, the fineness of the band cord is the sum of the finenesses of each single filament.

[0058] In this specification, the composition (cord structure) of the cord made of organic fiber is represented in accordance with "5.2 Method of indicating cord structure" of JIS L1017. When the band cord is composed of, for example, two single filaments (filaments) having a fineness of 1400 dtex twisted together, the cord structure of this band cord is represented by 1400 dtex / 2. And in this case, the fineness (dtex) of the band cord is 2800 dtex, which is the sum of the finenesses (1400 dtex) of each single filament.

[0059] [Measurement method] "Styrene content" is calculated by pyrolysis gas chromatography or NMR measurement ( 1 H-NMR and 13 C-NMR). Component amounts such as "styrene content" are different from physical property values such as complex elastic modulus (E*), and there are true values that do not depend on the measurement method. Therefore, it is preferable to use a measurement method with as high precision as possible. Note that in this specification, "pyrolysis gas chromatography" refers to a method in which a sample is heated by a pyrolysis device, the individual components contained in the gas-phase components generated by this heating are separated by a separation column, and each isolated component is analyzed.

[0060] "Vinyl content (amount of 1,2-bonded butadiene units)" is determined by pyrolysis gas chromatography or NMR measurement ( 1 H-NMR and 13It is calculated using 1C-NMR. Similar to "styrene content," a true value exists for "vinyl content" that is independent of the measurement method, so it is preferable to use the most accurate measurement method possible.

[0061] "Cis content (amount of cis-1,4-bonded butadiene units)" is determined by infrared absorption spectroscopy or NMR measurement in accordance with JIS K 6239-2:2017. 1 H-NMR and 13 This value is measured by 13C-NMR and is applied, for example, to rubber components having repeating units derived from butadiene, such as BR. Similar to "styrene content," a true value exists for "cis content" that is independent of the measurement method, so it is preferable to use the most accurate measurement method possible.

[0062] The "weight-average molecular weight (Mw)" can be determined by converting the measured value using gel permeation chromatography (GPC) (for example, the GPC-8000 series from Tosoh Corporation, with a differential refractometer as the detector and TSKgel SuperMultipore HZ-M column from Tosoh Corporation) to a standard polystyrene equivalent. This method is applicable, for example, to SBR, BR, etc.

[0063] The nitrogen adsorption specific surface area (N2SA) of carbon black is measured in accordance with JIS K 6217-2:2017.

[0064] The nitrogen adsorption specific surface area (N2SA) of silica is measured by the BET method in accordance with ASTM D3037-93.

[0065] The "average primary particle diameter" is a value obtained by photographing particles with a transmission or scanning electron microscope and calculating the arithmetic mean of the particle diameters of 400 particles. If the particle is spherical, the diameter of the sphere is used as the particle diameter; if it is not spherical, the equivalent diameter of a circle (the positive square root of {4 × (particle area) / π}) is calculated from the microscope image and used as the particle diameter.

[0066] A "plasticizer" is a material that imparts plasticity to rubber components and is extracted from rubber compositions using acetone. This definition includes both liquid plasticizers at 25°C and solid plasticizers at 25°C. However, it excludes waxes and stearic acid commonly used in the tire industry.

[0067] "Plasticizer content" includes the amount of plasticizer in the rubber component that has been stretched by the plasticizer.

[0068] [tire] A tire, which is one embodiment of the present invention, will be described below with reference to the drawings as appropriate. However, the drawings used are merely specific examples of one embodiment, and the present invention is not limited by these drawings.

[0069] The tire according to this embodiment is a tire comprising a band and a tire member made of a rubber composition containing recycled carbon black. The band includes at least one band ply in which a plurality of band cords made of polyethylene terephthalate fibers are arranged, and the thickness A (mm) of the tire member, the total amount B (parts by mass) of carbon black in the rubber composition, the number of band cords inserted C (cords / 50 mm), and the diameter D (mm) of the band cords satisfy the relationship given by formula (1).

[0070] Figure 1 is a schematic diagram showing a portion of the cross-section (upper right portion of the cross-section) of a tire according to one embodiment of the present invention, along the tire meridian. In Figure 1, the tire 1 has a base tread 5 on the radially inward side of the cap tread that constitutes the tread surface, and a band 6 further radially inward of the band 5. It also has a pair of sidewalls 3 arranged on both sides of the tread portion, and a clinch apex 2 arranged at the radially inward end of the sidewalls 3. The inner liner 4 constitutes the inner surface of the tire and maintains the internal pressure of the tire. In Figure 1, the thickness of the clinch apex 2 is indicated as T2, the thickness of the sidewall 3 as T3, the thickness of the inner liner 4 as T4, the thickness of the base tread 5 as T5, and the thickness of the insulation as T7.

[0071] (A) The value of A may be, for example, 0.1 mm or more, preferably 0.3 mm or more, more preferably 0.5 mm or more, even more preferably 0.7 mm or more, and even more preferably 1.0 mm or more. On the other hand, the value is preferably 10 mm or less, more preferably 9 mm or less, and even more preferably 8 mm or less.

[0072] The value of A can take the above values, but it may also vary depending on the type of tire component. For example, the thickness of the clinch apex is preferably 4 mm or more, more preferably 4.5 mm or more, and even more preferably 5 mm or more. There is no particular upper limit, but it is preferably 8 mm or less, more preferably 7 mm or less, and even more preferably 6 mm or less.

[0073] Furthermore, for example, the thickness of the base tread is preferably 0.3 mm or more, more preferably 0.4 mm or more, and even more preferably 0.5 mm or more. There is no particular upper limit, but it is preferably 7 mm or less, more preferably less than 5 mm, even more preferably 4 mm or less, and even more preferably 3 mm or less.

[0074] Furthermore, for example, the thickness of the inner liner is preferably 0.5 mm or more, more preferably 0.7 mm or more, and even more preferably 1 mm or more. There is no particular upper limit, but it is preferably 2.5 mm or less, more preferably 2 mm or less, and even more preferably 1.5 mm or less.

[0075] Furthermore, for example, the thickness of the sidewall is preferably 2 mm or more, more preferably 2.5 mm or more, and even more preferably 3 mm or more. There is no particular upper limit, but it is preferably 6 mm or less, more preferably 5.5 mm or less, and even more preferably 4 mm or less.

[0076] Furthermore, for example, the thickness of the insulation is preferably 0.1 mm or more, more preferably 0.5 mm or more, and even more preferably 0.7 mm or more. There is no particular upper limit, but it is preferably 2 mm or less, more preferably 1.5 mm or less, and even more preferably 1.0 mm or less.

[0077] (band) The tread portion of this embodiment is provided with a base tread 5 positioned on the inner side of the tire radially in contact with the ground, and a band 6 positioned further inward. In Figure 1, the band 6 is composed of a single band ply in which multiple band cords extending in the circumferential direction of the tire are arranged in the axial direction of the tire. The band consists of two outer regions located on the outer side in the axial direction of the tire, and a central region sandwiched between the two outer regions.

[0078] The band cord is made of polyethylene terephthalate fibers (PET fibers). PET fibers include recycled polyethylene terephthalate fibers. The band cord may consist solely of recycled polyethylene terephthalate fibers, or it may consist of recycled polyethylene terephthalate fibers and other polyethylene terephthalate fibers. The band cord may consist of a single PET fiber, or it may consist of two or more fibers twisted together. The fineness of the band cord is preferably 1000 dtex or more, more preferably 1500 dtex or more, and even more preferably 2000 dtex or more. Furthermore, the fineness of the band cord is preferably 7000 dtex or less, more preferably 5500 dtex or less, and even more preferably 4000 dtex or less. This improves the durability of the tire.

[0079] (C) In a cross section perpendicular to the longitudinal direction of the band cord, the number of band cords C (cords / 50mm) per 50mm ply width of the band ply is, for example, 30 or more, preferably 40 or more, more preferably 45 or more, and still preferably 50 or more. Also, C is, for example, 90 or less, preferably 80 or less, more preferably 75 or less, still preferably 70 or less, and still preferably 65 or less. The preferred range is 40 to 80 cords, and more preferably 45 to 75 cords. Having C within the above range improves the durability of the tire.

[0080] Band chords may be placed at equal intervals throughout the entire band, but for example, the spacing of band chords can be varied between the central and outer regions of the band. It is preferable that the number of band chords placed in the outer region of the band is greater than that in the central region.

[0081] (D) For D, for example, it is preferably greater than 0.2 mm, more preferably greater than 0.3 mm, and even more preferably 0.4 mm or more. Also, it is preferably less than 1.2 mm, more preferably less than 1.0 mm, even more preferably less than 0.9 mm, and even more preferably 0.8 mm or less. Being within this range improves the durability of the tire.

[0082] Furthermore, the band cord may consist of PET fibers of the same fineness, diameter, and stiffness arranged throughout the entire band, but for example, PET fibers with different fineness, diameter, and stiffness can be arranged in the central and outer regions of the band. It is preferable that the band cord be arranged such that the stiffness of the band cord in the outer region is higher than that of the band cord in the central region.

[0083] (Formula (1)) Formula (1) specifies that the quotient [D×C / (B×A)] obtained by dividing the product of the diameter D of the band cord and the number of band cords inserted C by the product of the total amount of carbon black B and the thickness A of the tire member is greater than 0.07 and less than 0.60. The value of D×C / (B×A) is preferably greater than 0.10, more preferably greater than 0.13, even more preferably greater than 0.16, even more preferably greater than 0.18, and even more preferably greater than 0.20. Also, the value of D×C / (B×A) is preferably less than 0.58, more preferably less than 0.55, even more preferably less than 0.52, even more preferably less than 0.50, even more preferably less than 0.48, and even more preferably less than 0.45.

[0084] A preferred range for the value of D×C / (B×A) is, for example, greater than 0.13 and less than 0.58; a more preferred range is greater than 0.16 and less than 0.55; an even more preferred range is greater than 0.18 and less than 0.55; and an even more preferred range is greater than 0.20 and less than 0.52.

[0085] Regarding equation (1), A can be adjusted by increasing or decreasing the thickness of the tire component made of a rubber composition containing recycled carbon black, and B can be adjusted by increasing or decreasing the total amount of carbon black, including recycled carbon black, in the rubber composition. C can be adjusted by increasing or decreasing the number of band cords per band ply width, and D can be adjusted by increasing or decreasing the diameter of the band cords. When C or D increases, the value of D × C / (B × A) increases, and conversely, when they decrease, the same value decreases. Similarly, when A or B increases, the value of D × C / (B × A) decreases, and conversely, when they decrease, the same value increases.

[0086] (G / W L ) In this embodiment, G / W L It is preferable that the ratio is 0.0135 or less. Such tires are lightweight tires in which the tire weight is relatively light relative to the tire's maximum load capacity, and it is believed that the tire's durability is improved. In this embodiment, G / W LIt is more preferable that the value be 0.0130 or less, and even more preferable that it be 0.0128 or less.

[0087] Golden Week L This can be adjusted by changing the tire weight and tire size.

[0088] [Rubber composition] The rubber composition used for tire components constituting the tire according to the present invention will now be described. In the embodiments of the present invention, at least one of the components constituting the tire contains recycled carbon black in its rubber composition. In preferred embodiments, tire components composed of a rubber composition containing recycled carbon black include the clinch apex, base tread, inner liner, sidewall, and insulation. The rubber composition containing recycled carbon black according to this embodiment can also be used for cord topping rubber.

[0089] Hereinafter, the rubber compositions used in tire components according to one embodiment, specifically the rubber compositions constituting the clinch apex, base tread, inner liner, and sidewall, will be described assuming they contain recycled carbon black. If the rubber compositions used in tire components do not contain recycled carbon black, the descriptions relating to recycled carbon black may be read as descriptions relating to ordinary carbon black other than recycled carbon black.

[0090] [Rubber composition for clinch apex] The components of the rubber composition for clinch apex will now be described. It is preferable that at least one tire component made of the rubber composition containing recycled carbon black is a clinch apex.

[0091] <Rubber components> The rubber composition contains a rubber component, preferably at least one of isoprene rubber (IR rubber), styrene-butadiene rubber (SBR), and butadiene rubber (BR). In this case, the rubber component may include rubber components other than isoprene rubber, SBR, and BR. In one embodiment, it is more preferable that the rubber component includes isoprene rubber and BR. In addition to isoprene rubber and BR, other rubber components may be included, or the composition may consist only of isoprene rubber and BR.

[0092] (Isoprene rubber) As isoprene-based rubbers, for example, isoprene rubber (IR) and natural rubber, which are common in the tire industry, can be used. Natural rubber includes not only unmodified natural rubber (NR), but also modified natural rubbers such as epoxidized natural rubber (ENR), hydrogenated natural rubber (HNR), deproteinized natural rubber (DPNR), high-purity natural rubber (UPNR), and grafted natural rubber. These isoprene-based rubbers may be used individually or in combination of two or more types.

[0093] NR is not particularly limited and can be any that is common in the tire industry, such as SIR20, RSS#3, TSR20, etc.

[0094] The content of isoprene-based rubber in the rubber component is, for example, more than 10% by mass, preferably more than 20% by mass, more preferably more than 30% by mass, even more preferably more than 35% by mass, and even more preferably 40% by mass or more. Furthermore, the content is preferably 80% by mass or less, more preferably less than 70% by mass, even more preferably less than 65% by mass, and even more preferably less than 60% by mass.

[0095] (SBR) There are no particular limitations on the type of SBR used; solution-polymerized SBR (S-SBR), emulsion-polymerized SBR (E-SBR), and modified SBRs thereof (modified S-SBR, modified E-SBR) can be used. Examples of modified SBRs include SBRs with modified terminals and / or main chains, and modified SBRs coupled with tin, silicon compounds, etc. (condensates, branched structures, etc.). Furthermore, hydrogenated versions of these SBRs (hydrogenated SBRs) can also be used. SBRs may be used individually or in combination of two or more types.

[0096] The functional groups that the modified SBR has are preferably functional groups containing at least one element selected from the group consisting of silicon, nitrogen, and oxygen. Examples of such functional groups include amino groups, amide groups, silyl groups, alkoxysilyl groups, isocyanate groups, imino groups, imidazole groups, urea groups, ether groups, carbonyl groups, oxycarbonyl groups, mercapto groups, sulfide groups, disulfide groups, sulfonyl groups, sulfinyl groups, thiocarbonyl groups, ammonium groups, imide groups, hydrazo groups, azo groups, diazo groups, carboxyl groups, nitrile groups, pyridyl groups, alkoxy groups (preferably alkoxy groups having 1 to 6 carbon atoms), hydroxyl groups, oxy groups, epoxy groups, etc., with amino groups and / or alkoxysilyl groups being preferred. As for amino groups, amino groups substituted with 1 to 2 alkyl groups having 1 to 6 carbon atoms are preferred. Specific examples of alkoxysilyl groups include, for example, trimethoxysilyl, triethoxysilyl, triisopropoxysilyl, dimethoxymethylsilyl, diethoxymethylsilyl, dimethylmethoxysilyl, and dimethylethoxysilyl.

[0097] As the SBR, either oil-expanded SBR or non-oil-expanded SBR can be used. In this specification, as the SBR, commercially available products from JSR Corporation, Sumitomo Chemical Co., Ltd., UBE Corporation, Asahi Kasei Corporation, ZS Elastomer Corporation, ARLANXEO, etc. can be used.

[0098] From the viewpoint of rubber strength and grip performance, the styrene content of SBR is preferably more than 10% by mass, more preferably more than 15% by mass, and even more preferably more than 20% by mass. Furthermore, from the viewpoint of low fuel consumption, the styrene content is preferably less than 55% by mass, more preferably less than 50% by mass, and even more preferably less than 45% by mass. Note that the styrene content of SBR is the value calculated by the measurement method described above.

[0099] From the viewpoint of rubber strength and grip performance, the vinyl content of SBR is preferably more than 10 mol%, more preferably more than 15 mol%, and even more preferably more than 18 mol%. Furthermore, from the viewpoint of low fuel consumption, the vinyl content is preferably less than 80 mol%, more preferably less than 70 mol%, and even more preferably less than 65 mol%. Note that the vinyl content of SBR is the value measured by the measurement method described above.

[0100] The weight-average molecular weight (Mw) of SBR is preferably 100,000 or more, more preferably 150,000 or more, and even more preferably 190,000 or more, from the viewpoint of low fuel consumption performance. Furthermore, from the viewpoint of crosslinking uniformity, the Mw is preferably 2,500,000 or less, and more preferably 2,000,000 or less. The Mw of SBR is measured by the measurement method described above.

[0101] When SBR is included, the SBR content in 100% by mass of the rubber component is preferably less than 20% by mass, more preferably less than 15% by mass, and even more preferably less than 10% by mass. There is no particular limit to the lower limit of the content; for example, it may be 1% by mass.

[0102] (BR) BR is not particularly limited, and for example, BR with a cis content of less than 50 mol% (low-cis BR), BR with a cis content of 90 mol% or more (high-cis BR), rare-earth butadiene rubber synthesized using a rare-earth element catalyst (rare-earth BR), BR containing syndiotactic polybutadiene crystals (SPB-containing BR), modified BR (high-cis modified BR, low-cis modified BR), etc., which are common in the tire industry, can be used. BR may be used alone or in combination of two or more types.

[0103] High-cis BR can be commercially available from companies such as Nippon Zeon Co., Ltd., UBE Corporation, and JSR Corporation. Including high-cis BR can improve low-temperature properties and wear resistance. The cis content of high-cis BR is preferably more than 90 mol%, more preferably more than 95 mol%, and even more preferably 96 mol% or more. The cis content of BR is measured by the measurement method described above.

[0104] Rare earth-based BR is synthesized using a rare earth element catalyst, and has a vinyl content of preferably less than 1.8 mol%, more preferably less than 1.5 mol%, and even more preferably less than 1.2 mol%, and a cis content of preferably more than 90 mol%, more preferably more than 95 mol%, and even more preferably 96 mol% or more. As rare earth-based BR, commercially available products from companies such as Lanxess can be used.

[0105] SPB-containing BR refers to a type in which 1,2-syndiotactic polybutadiene crystals are not simply dispersed in BR, but are chemically bonded to and dispersed in BR. Such SPB-containing BR can be commercially available from companies such as UBE Corporation.

[0106] Examples of modified BR include BR modified with functional groups similar to those described for SBR above, as well as modified butadiene rubber (modified BR) in which the terminal and / or main chain is modified with functional groups containing at least one element selected from the group consisting of silicon, nitrogen, and oxygen.

[0107] Other modified BRs include those obtained by polymerizing 1,3-butadiene with a lithium initiator and then adding a tin compound, and in which the ends of the modified BR molecule are linked by a tin-carbon bond (tin-modified BR). Furthermore, the modified BR may be either unhydrogenated or hydrogenated.

[0108] The weight-average molecular weight (Mw) of BR is preferably greater than 300,000, more preferably greater than 350,000, and even more preferably greater than 400,000. Furthermore, from the viewpoint of crosslinking uniformity, it is preferably less than 2,000,000, more preferably less than 1,000,000, and even more preferably less than 700,000. The Mw of BR can be determined by the method described above.

[0109] The content of BR in the rubber component is, for example, more than 10% by mass, preferably 20% by mass or more, more preferably more than 30% by mass, even more preferably more than 35% by mass, and even more preferably more than 40% by mass. Furthermore, the content is preferably less than 80% by mass, more preferably less than 70% by mass, even more preferably less than 65% by mass, and even more preferably 60% by mass or less.

[0110] The total content of isoprene-based rubber and BR in 100% by mass of the rubber component is preferably more than 80% by mass, more preferably more than 90% by mass, and even more preferably more than 95% by mass, and may be 100% by mass.

[0111] (Other rubber components) In addition to the isoprene-based rubbers, SBR, and BR mentioned above, the rubber components may include other rubber components. Such rubber components may include crosslinkable rubber components commonly used in the tire industry. More specifically, examples include diene-based rubbers such as styrene-isoprene-butadiene copolymer rubber (SIBR), styrene-isobutylene-styrene block copolymer (SIBS), chloroprene rubber (CR), and acrylonitrile-butadiene rubber (NBR), as well as non-diene rubbers such as butyl rubber (IIR), ethylene propylene rubber, polynorbornene rubber, silicone rubber, polyethylene chloride rubber, fluororubber (FKM), acrylic rubber (ACM), and hydrin rubber. These other rubber components may be used individually or in combination of two or more. Furthermore, known thermoplastic elastomers may also be included in addition to the above-mentioned rubber components.

[0112] (Rubber components synthesized from recycled and biomass-derived raw materials) Monomers, which are the constituent units of synthetic rubbers such as IR, SBR, and BR, may be derived from underground resources such as petroleum and natural gas, or they may be recycled from rubber products such as tires or non-rubber products such as polystyrene. The monomers obtained by recycling (recycled monomers) are not particularly limited, but include recycled polyisoprene, recycled butadiene, and recycled aromatic vinyl compounds. Examples of butadiene include 1,2-butadiene and 1,3-butadiene. Examples of aromatic vinyl compounds are not particularly limited, but include styrene. In particular, it is preferable to use recycled polyisoprene (recycled isoprene), recycled butadiene (recycled butadiene), and / or recycled styrene (recycled styrene) as raw materials.

[0113] The method for producing recycled monomer is not particularly limited, and for example, it can be synthesized from recycled naphtha obtained by decomposing rubber products such as tires. Furthermore, the method for producing recycled naphtha is not particularly limited, and for example, rubber products such as tires may be decomposed under high temperature and pressure, decomposed by microwaves, or extracted after mechanical grinding.

[0114] Furthermore, the monomers that make up polymers such as IR, SBR, and BR may be derived from biomass. In this specification, biomass refers to substances derived from natural resources such as plants. Biomass is not particularly limited, but examples include agricultural, forestry, and fishery products, sugars, wood chips, plant residues after obtaining useful components, plant-derived ethanol, and biomass naphtha.

[0115] The biomass-derived monomer (biomass monomer) is not particularly limited and includes biomass-derived butadiene and biomass-derived aromatic vinyl compounds. Examples of the butadiene include 1,2-butadiene and 1,3-butadiene. Examples of the aromatic vinyl compound are not particularly limited but include styrene. Furthermore, the method for producing the biomass monomer is not particularly limited and includes, for example, biological and / or chemical and / or physical transformations of plants and animals. Typical biological transformations include fermentation by microorganisms, while chemical and / or physical transformations include those by catalysts, high heat, high pressure, electromagnetic waves, critical liquids, and combinations thereof.

[0116] The polymer synthesized from biomass monomer components (biomass polymer) is not particularly limited, and examples include polybutadiene rubber synthesized from biomass-derived butadiene, and aromatic vinyl / butadiene copolymers synthesized from biomass-derived butadiene and / or biomass-derived aromatic vinyl compounds. Examples of the aromatic vinyl / butadiene copolymer include styrene-butadiene rubber synthesized from biomass-derived butadiene and / or biomass-derived styrene.

[0117] Whether the raw materials for a polymer are biomass-derived can be determined by measuring pMC (percent Modern Carbon) according to ASTM D6866-10. pMC refers to the percentage of modern standard reference carbon. 14 Sample relative to C concentration 14 This is a ratio of C concentrations and is used as an indicator of the biomass ratio of a compound. The significance of this value is described below.

[0118] 1 mole of carbon atoms (6.02 × 10⁻¹⁰) 23 (Each) contains approximately 6.02 × 10¹⁶ atoms, which is about one trillionth of the amount of carbon atoms in a normal atom. 11 individual 14 C exists. 14The half-life of C is 5730 years. 14 C is decreasing regularly. Therefore, in fossil fuels such as coal, oil, and natural gas, which are thought to have been fixed after more than 226,000 years have passed since atmospheric carbon dioxide was taken in and fixed by plants, etc., C was initially included in these as well. 14 All elements of C have decayed. Therefore, in the 21st century, fossil fuels such as coal, oil, and natural gas are no longer viable. 14 It contains absolutely no element C. Therefore, chemical substances produced using these fossil fuels as raw materials also contain C. 14 It contains absolutely no element C.

[0119] on the other hand, 14 C is continuously produced when cosmic rays undergo nuclear reactions in the atmosphere. Therefore, 14 In the Earth's atmospheric environment, carbon (C) is produced in a state where its decrease due to radioactive decay and its production through nuclear reactions are in equilibrium. 14 The amount of C is constant. Therefore, the amount of biomass resource-derived substances currently circulating in the environment 14 As mentioned above, the carbon concentration is approximately 1 × 10¹⁶ of the total carbon atoms. -12 These values ​​are approximately in mole percent. Therefore, the difference between these values ​​can be used to calculate the biomass ratio in a given compound.

[0120] this 14 C is typically measured as follows: Using accelerator mass spectrometry based on a tandem accelerator, 13 C concentration ( 13 C / 12 C), 14 C concentration ( 14 C / 12 Perform measurement C). In the measurement, 14 As a modern standard reference for the concentration of C, the amount of cyclic carbon in nature as of 1950 14The C concentration will be used. The specific standard material will be the oxalic acid standard provided by NIST (National Institute of Standards and Technology). The specific radioactivity of carbon in this oxalic acid (per gram of carbon) will be used. 14 The radioactivity intensity of C is separated by carbon isotope, 13 The standard value is obtained by correcting C to a constant value and applying decay correction from 1950 AD to the measurement date. 14 This value is used as the C concentration value (100%). The ratio of this value to the value of the sample actually measured is the pMC value.

[0121] Therefore, if rubber is made from 100% biomass-derived materials, although there are regional differences, under normal conditions it will often not reach 100, and will show a value of approximately 110 pMC. On the other hand, regarding chemical substances derived from fossil fuels such as petroleum, 14 When the C concentration is measured, it will show a value of approximately 0 pMC (for example, 0.3 pMC). This value corresponds to the aforementioned biomass ratio of 0%.

[0122] Based on the above, using materials such as rubber with a high pMC value, that is, materials such as rubber with a high biomass ratio, in rubber compositions is preferable from an environmental protection standpoint.

[0123] <Filler> The above-mentioned rubber composition for tire components contains recycled carbon black as a filler. The filler refers to a reinforcing filler and may contain recycled carbon black (rCB), ordinary carbon black, silica, or other reinforcing fillers used in the tire industry, but it may also be a filler consisting only of silica and carbon black. Furthermore, if the filler contains silica, it may also contain a silane coupling agent. The filler may be used alone or in combination of two or more types.

[0124] (Recycled carbon black) "Recycled carbon black" refers to carbon black obtained by crushing used tires and other products containing carbon black, and calcining the crushed material, wherein, according to the thermogravimetric method compliant with JIS K 6226-2:2003, when oxidative combustion occurs by heating in air, the proportion of the unburned component, ash (ash content), is 13% by mass or more. In other words, the proportion of the mass (carbon content) lost due to the aforementioned oxidative combustion of recycled carbon black is 87% by mass or less. The ash content of recycled carbon black is preferably 14% by mass or more, more preferably 15% by mass or more, even more preferably 16% by mass or more, and even more preferably 17% by mass or more. Recycled carbon black is sometimes represented as rCB.

[0125] Recycled carbon black can be obtained from the pyrolysis process of used pneumatic tires. For example, European Patent Application Publication No. 3427975, which refers to "Rubber Chemistry and Technology," Vol. 85, No. 3, pp. 408-449 (2012), particularly pp. 438, 440, and 442, states that it can be obtained by the pyrolysis of organic materials at 550-800°C in the absence of oxygen, or by vacuum pyrolysis at relatively low temperatures (

[0027] ). Carbon black obtained from such pyrolysis processes usually lacks functional groups on its surface, as referred to in

[0004] of Japanese Patent Publication No. 6856781 (Comparison of Surface Morphology and Chemistry of Pyrolysis Carbon Black and Commercial Carbon Black, Powder Technology 160 (2005) 190-193).

[0126] Recycled carbon black may lack functional groups on its surface, or it may be treated to include functional groups on its surface. Treatment to include functional groups on the surface of recycled carbon black can be carried out by conventional methods. For example, in European Patent Application Publication No. 3173251, carbon black obtained from a pyrolysis process is treated with potassium permanganate under acidic conditions to obtain carbon black containing hydroxyl and / or carboxyl groups on its surface. In addition, in Japanese Patent Publication No. 6856781, carbon black obtained from a pyrolysis process is treated with an amino acid compound containing at least one thiol group or disulfide group to obtain carbon black with an activated surface. The recycled carbon black according to this embodiment also includes carbon black treated to include functional groups on its surface.

[0127] Recycled carbon black can be commercially available from companies such as Strable Green Carbon, LD Carbon, and Enrestec. For example, Enrestec's product name PB365 is recycled carbon black produced through the thermal decomposition of waste tires, and has an N2SA of 76m. 2 It is / g. Also, PB365 contains approximately 17% by mass of ash.

[0128] The average primary particle size of recycled carbon black is not particularly limited, but is usually between 10 nm and 100 nm. The lower limit is preferably 12 nm or more, more preferably 20 nm or more, even more preferably 30 nm or more, and particularly preferably 40 nm or more, while the upper limit is preferably 90 nm or less, more preferably 80 nm or less, and even more preferably 70 nm or less. The average primary particle size of the carbon black is measured by the measurement method described above.

[0129] (Carbon black other than rCB) Other carbon blacks besides recycled carbon black (regular carbon blacks) are not particularly limited and include N134, N110, N220, N234, N219, N339, N330, N326, N351, N550, N762, etc. The raw materials for carbon black may be biomass materials such as lignin and vegetable oil, or pyrolysis oil obtained by thermal decomposition of waste tires. The manufacturing method for carbon black may be combustion such as the furnace method, hydrothermal carbonization (HTC), or thermal decomposition of methane such as the thermal black method. Commercially available products include those from Asahi Carbon Co., Ltd., Cabot Japan Co., Ltd., Tokai Carbon Co., Ltd., Mitsubishi Chemical Corporation, Lion Corporation, Nippon Steel Carbon Co., Ltd., Columbia Carbon Corporation, etc. Carbon black may be used alone or in combination of two or more types.

[0130] In addition to the above, from the perspective of life cycle assessment, carbon black made from biomass materials such as lignin, or recycled carbon black refined by thermal decomposition of carbon black-containing products such as tires, may also be used as carbon black.

[0131] The nitrogen adsorption specific surface area (N2SA) of carbon black is 50m², considering its weather resistance and reinforcing properties. 2 Preferably more than / g, 80m 2 More preferably than / g, 100m 2 A value exceeding / g is even more preferable. Furthermore, N2SA is preferable in terms of dispersibility, low fuel consumption performance, fracture characteristics and durability, at 250m 2 Preferably less than / g, 220m 2 Less than / g is more preferable, 180m 2 It is even more preferable that the amount be less than / g, and 150m 2 A value of less than / g is even more preferable. The N2SA of carbon black is measured by the measurement method described above.

[0132] The average primary particle size of carbon black is preferably greater than 12 nm, more preferably greater than 15 nm, and even more preferably greater than 17 nm, from the viewpoint of weather resistance and reinforcing properties. Furthermore, from the viewpoint of dispersibility, low fuel consumption performance, fracture characteristics, and durability, the average primary particle size is preferably less than 30 nm, more preferably less than 25 nm, and even more preferably 22 nm or less. The average primary particle size of carbon black is measured by the measurement method described above.

[0133] Total amount of carbon black B The total amount (parts by mass) of carbon black, including recycled carbon black, is preferably 25 parts by mass or more, more preferably 35 parts by mass or more, and even more preferably 45 parts by mass or more, per 100 parts by mass of rubber component. On the other hand, the total amount is preferably less than 85 parts by mass, more preferably less than 80 parts by mass, even more preferably less than 75 parts by mass, and even more preferably 70 parts by mass or less. When the total amount of carbon black is within the above range, sufficient reinforcing properties, good dispersion in the rubber, and sufficient rubber strength and durability tend to be obtained.

[0134] <<Recycled carbon black content>> From the viewpoint of the effects of the present invention, the content of recycled carbon black in relation to the carbon black content is preferably more than 5% by mass, more preferably more than 10% by mass, even more preferably more than 15% by mass, and even more preferably 20% by mass or more. On the other hand, from the viewpoint of reinforcing properties, it is preferably less than 50% by mass, more preferably less than 40% by mass, even more preferably less than 35% by mass, even more preferably less than 30% by mass, and even more preferably less than 25% by mass.

[0135] <Other fillers> The filler may include other fillers besides carbon black, including recycled carbon black. While not particularly limited, other fillers commonly used in the tire industry, such as silica, aluminum hydroxide, calcium carbonate, alumina, clay, and talc, can be included. If silica is included, it is preferable to use it in combination with a silane coupling agent.

[0136] (silica) When the above rubber composition contains silica, the silica is not particularly limited, and common types used in the tire industry can be used, such as silica prepared by a dry process (anhydrous silica) or silica prepared by a wet process (hydrated silica). The raw material for silica is not particularly limited, and may be a mineral-derived raw material such as quartz, or a biological-derived raw material such as rice husks (for example, silica made from biomass materials such as rice husks), or silica recycled from silica-containing products may be used. Among these, hydrated silica prepared by a wet process is preferred because it has a high silanol group content. Silica may be used alone or in combination of two or more types.

[0137] Silica derived from biomass materials can be obtained, for example, by extracting silicates from rice husk ash obtained by burning rice husks using a sodium hydroxide solution, and then using these silicates to react with sulfuric acid in the same way as conventional wet silica, the precipitate of silicon dioxide is filtered, washed with water, dried, and pulverized.

[0138] The silica recycled from silica-containing products can be, for example, silica recovered from products containing silica such as semiconductors and other electronic components, tires, desiccants, and diatomaceous earth and other filter materials. The recovery method is not particularly limited and can include thermal decomposition and decomposition by electromagnetic waves. Among these, silica recovered from semiconductors and other electronic components or tires is preferred.

[0139] When silica crystallizes, it becomes insoluble in water, and its component, silicic acid, cannot be utilized. By controlling the combustion temperature and combustion time, the crystallization of silica in rice husk ash can be suppressed (see Japanese Patent Publication No. 2009-2594, Akita Prefectural University Web Journal B / 2019, vol.6, pp.216-222, etc.). Amorphous silica extracted from rice husks can be commercially available from companies such as Wilmar.

[0140] The specific surface area (N2SA) of silica for nitrogen adsorption is not particularly limited, but from the viewpoint of reinforcing properties, 130m² is considered to be the optimal value. 2 Preferably more than / g, 150m 2 More preferably than / g, 170m 2 A value exceeding / g is even more preferable. Also, N2SA is preferable to 500m from the viewpoint of processability. 2 Preferably less than / g, 350m 2 Less than / g is more preferable, 300m 2 A value less than / g is even more preferable. The N2SA of silica is the value measured by the measurement method described above.

[0141] When silica is included, the silica content is more than 10 parts by mass per 100 parts by mass of rubber component, preferably more than 15 parts by mass, more preferably more than 20 parts by mass, and even more preferably more than 30 parts by mass. Furthermore, the silica content is preferably less than 60 parts by mass, more preferably less than 55 parts by mass, and even more preferably less than 50 parts by mass.

[0142] (Silane coupling agent) Silane coupling agents are not particularly limited, but include, for example, sulfide-based silane coupling agents such as bis(3-triethoxysilylpropyl) disulfide and bis(3-triethoxysilylpropyl) tetrasulfide; silane coupling agents having a mercapto group such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, and 2-mercaptoethyltriethoxysilane; vinyl-based silane coupling agents such as vinyltriethoxysilane and vinyltrimethoxysilane; and 3-aminopropyltriethoxysilane and 3-aminopropyltrimethoxysilane. Examples of silane coupling agents include amino-based silane coupling agents such as 3-(2-aminoethyl)aminopropyltriethoxysilane; glycidoxy-based silane coupling agents such as γ-glycidoxypropyltriethoxysilane and γ-glycidoxypropyltrimethoxysilane; nitro-based silane coupling agents such as 3-nitropropyltrimethoxysilane and 3-nitropropyltriethoxysilane; and chloro-based silane coupling agents such as 3-chloropropyltrimethoxysilane and 3-chloropropyltriethoxysilane. Among these, it is preferable to contain a sulfide-based silane coupling agent and / or a silane coupling agent having a mercapto group. As silane coupling agents, for example, those commercially available from Evonik Degussa, Momentive, etc., can be used. The silane coupling agent may be used alone or in combination of two or more.

[0143] From the viewpoint of improving silica dispersibility, the content of the silane coupling agent per 100 parts by mass of silica is preferably 1 part by mass or more, more preferably 3 parts by mass or more, even more preferably 5 parts by mass or more, and even more preferably 8 parts by mass or more. Furthermore, from the viewpoint of cost and processability, it is preferably 20 parts by mass or less, more preferably 18 parts by mass or less, and even more preferably 16 parts by mass or less.

[0144] <Other compounding agents> In addition to rubber components and fillers, the rubber composition may appropriately contain compounding agents commonly used in the tire industry, such as plasticizers, vulcanized rubber particles (rubber powder), antioxidants, waxes, processing aids, stearic acid, zinc oxide, vulcanizing agents, and vulcanization accelerators.

[0145] <Plasticizer> A plasticizer is a material that imparts plasticity to rubber components, and the concept includes both liquid and solid plasticizers at 25°C. Examples of plasticizers include resin components, oils, liquid rubber, and ester-based plasticizers. These plasticizers may be derived from mineral resources such as petroleum and natural gas, from biomass, or from naphtha recycled from rubber or non-rubber products. Low molecular weight hydrocarbon components obtained by thermal decomposition and extraction of used tires or products containing various components may also be used as plasticizers. Plasticizers may be used individually or in combination of two or more types.

[0146] (Resin components) The rubber composition according to this embodiment may also contain a resin component. The resin component that can be used in this embodiment is not particularly limited, but resins commonly used in the tire industry can be used, such as C9 resins, C5 resins, C5C9 resins, dicyclopentadiene resins, aromatic vinyl resins, coumarone resins, indene resins, terpene resins, rosin resins, phenolic resins, etc. These resin components may be used individually or in combination of two or more. Each resin component may also be used individually or in combination of two or more.

[0147] ≪C9 series resin≫ A "C9 resin" refers to a resin obtained by polymerizing a C9 fraction, and may be a polymer obtained by polymerizing the C9 fraction alone, or a copolymer obtained by copolymerizing the C9 fraction with other components. For example, a resin obtained by copolymerizing dicyclopentadiene (DCPD) and a C9 fraction is called a DCPD / C9 resin. Furthermore, the C9 resin may be a hydrogenated or modified version of these resins. Examples of C9 fractions include petroleum fractions with 8 to 10 carbon atoms, such as vinyltoluene, alkylstyrene, coumarone, indene, methylindene, and dicyclopentadiene. As for C9 resins, commercially available products from companies such as BASF, Zeon Corporation, and ENEOS Corporation can be used.

[0148] ≪C5 series resin≫ "C5 resins" refer to resins obtained by polymerizing C5 fractions, and may be hydrogenated or modified resins. Examples of C5 fractions other than dicyclopentadiene include petroleum fractions with 4 to 5 carbon atoms, such as cyclopentadiene, isoprene, piperylene, 2-methyl-1-butene, 2-methyl-2-butene, and 1-pentene. As C5 resins, commercially available products from companies such as Structol, Nippon Zeon Co., Ltd., and ENEOS Corporation can be used.

[0149] ≪C5C9 resin≫ "C5C9 resin" refers to a resin obtained by copolymerizing the C5 fraction and the C9 fraction, and may be hydrogenated or modified. As C5C9 petroleum resin, commercially available products from companies such as Tosoh Corporation and LUHUA can be used.

[0150] <Dicyclopentadiene resins> A "dicyclopentadiene-based resin" refers to a resin in which cyclopentadiene (CPD) and / or dicyclopentadiene (DCPD) are the most abundant monomer components, and these may be hydrogenated or modified resins. Preferred dicyclopentadiene-based resins include polymers obtained by polymerizing only dicyclopentadiene as a monomer, and copolymers (DCPD / C9 resins) obtained by copolymerizing dicyclopentadiene with the C9 fraction. Commercially available dicyclopentadiene-based resins from companies such as ExxonMobil, ENEOS Corporation, Nippon Zeon Corporation, and Maruzen Petrochemical Co., Ltd. can be used.

[0151] Aromatic vinyl resin "Aromatic vinyl resin" refers to a resin in which aromatic vinyl compounds such as styrene, α-methylstyrene, vinyltoluene, and p-chlorostyrene are the most abundant monomer components, and these may be hydrogenated or modified. As aromatic vinyl resins, α-methylstyrene or a homopolymer of styrene or a copolymer of α-methylstyrene and styrene is preferred, and a copolymer of α-methylstyrene and styrene is more preferred, for reasons of being economical, easy to process, and having excellent heat generation properties. As aromatic vinyl resins, commercially available products from companies such as Kraton, Eastman Chemical Company, and Mitsui Chemicals, Inc. can be used.

[0152] Coumaron-based resin "Coumarone-based resin" refers to a resin containing coumarone as a monomer component, and may be hydrogenated or modified. Preferred coumarone-based resins include, for example, coumarone resin, which is a polymer with coumarone as the monomer component; coumarone-indene resin, which is a copolymer with coumarone and indene as monomer components; and coumarone-indene-styrene resin, which is a copolymer with coumarone, indene, and styrene as monomer components. As coumarone-based resins, commercially available products from companies such as Rutgers, Nippon Paint Chemical Co., Ltd., and Mitsui Chemicals, Inc. can be used.

[0153] Indene resin "Indene-based resin" refers to a resin containing indene as a monomer component, and may be hydrogenated or modified resins. Preferred indene-based resins include, for example, coumarone-indene resin, which is a copolymer of coumarone and indene as monomer components, and coumarone-indene-styrene resin, which is a copolymer of coumarone, indene, and styrene as monomer components. Commercially available indene-based resins from companies such as Rutgers, Nippon Paint Chemical Co., Ltd., and Mitsui Chemicals, Inc. can be used.

[0154] Terpene resins "Terpene resin" refers to a resin containing terpene compounds such as α-pinene, β-pinene, limonene, and dipentene as monomer components, and may be hydrogenated or modified. Preferred terpene resins include, for example, polyterpene resins, which are polymers in which one or more of the aforementioned terpene compounds are used as monomer components; aromatically modified terpene resins, which are copolymers in which the aforementioned terpene compounds and aromatic compounds are used as monomer components; and terpene phenol resins, which are copolymers in which the aforementioned terpene compounds and phenol compounds are used as monomer components. Examples of aromatic compounds that serve as monomer components in aromatically modified terpene resins include styrene, α-methylstyrene, vinyltoluene, and divinyltoluene. Examples of phenol compounds that serve as monomer components in terpene phenol resins include phenol, bisphenol A, cresol, and xylenol. As terpene resins, commercially available products from companies such as Yasuhara Chemical Co., Ltd., Arakawa Chemical Industries, Ltd., and Nippon Terpene Chemical Co., Ltd. can be used.

[0155] ≪Rosin-based resin≫ "Rosin-based resin" refers to a resin containing rosin acid compounds such as abietic acid, neoabietic acid, palastic acid, and isopimal acid, and may be hydrogenated or modified. Rosin-based resins are not particularly limited, but examples include natural resin rosin and rosin-modified resins obtained by hydrogenating, disproportionating, dimerizing, esterifying, etc. As rosin-based resins, commercially available products from companies such as Harima Chemical Industries, Ltd., Arakawa Chemical Industries, Ltd., and IREC Co., Ltd. can be used.

[0156] Phenolic resins "Phenol-based resins" refer to resins containing phenol compounds such as phenol and cresol as monomer components, and may also be hydrogenated or modified resins. Phenolic resins are not particularly limited, but examples include phenol-formaldehyde resins, alkylphenol-formaldehyde resins, alkylphenol-acetylene resins, oil-modified phenol-formaldehyde resins, and terpene-phenol resins. Phenolic resins that are commercially available from companies such as Sumitomo Bakelite Co., Ltd., DIC Corporation, and Asahi Organic Materials Co., Ltd. can be used.

[0157] ≪Content≫ The content of the resin component per 100 parts by mass of the rubber component is preferably more than 1 part by mass, more preferably more than 5 parts by mass, and even more preferably 5 parts by mass or more. On the other hand, from the viewpoint of suppressing heat generation, the content is preferably less than 60 parts by mass, more preferably less than 30 parts by mass, and even more preferably less than 20 parts by mass.

[0158] (Plasticizers other than resin components) This section explains plasticizers other than resin components, such as oils, liquid rubbers, and ester-based plasticizers.

[0159] ≪Oil≫ Examples of oils include mineral oil, vegetable oil, and animal oil. Furthermore, from a life cycle assessment perspective, waste oil from rubber mixers and engines, or refined waste cooking oil from restaurants, may also be used. Oils may be used individually or in combination of two or more types.

[0160] In this specification, mineral oil refers to oil derived from mineral resources such as petroleum and natural gas. Examples of mineral oil include paraffinic oils (mineral oil), naphthenic oils, and aromatic oils. Specific examples of mineral oil include MES (Mild Extracted Solvate), DAE (Distillate Aromatic Extract), TDAE (Treated Distillate Aromatic Extract), TRAE (Treated Residual Aromatic Extract), and RAE (Residual Aromatic Extract). Furthermore, for environmental reasons, oils with a low content of polycyclic aromatic compounds (PCA) can be used. Examples of low-PCA oils include MES, TDAE, and heavy naphthenic oils. Mineral oil may be used alone or in combination of two or more types.

[0161] In this specification, vegetable oils include, for example, linseed oil, rapeseed oil, safflower oil, soybean oil, corn oil, cottonseed oil, rice oil, tall oil, sesame oil, perilla oil, castor oil, tung oil, pine oil, pine tar oil, sunflower oil, coconut oil, palm oil, palm kernel oil, olive oil, camellia oil, jojoba oil, macadamia nut oil, peanut oil, grapeseed oil, and wood wax. Furthermore, vegetable oils may also include refined oils (such as salad oil) obtained by refining the above oils, transesterified oils obtained by transesterifying the above oils, hydrogenated oils obtained by hydrogenating the above oils, thermally polymerized oils obtained by thermally polymerizing the above oils, oxidized polymerized oils obtained by oxidizing the above oils, and waste cooking oils recovered from use as edible oils. Note that vegetable oils may be liquid or solid at 25°C. Vegetable oils may be used individually or in combination of two or more types.

[0162] The vegetable oil preferably contains acylglycerol, and more preferably contains triacylglycerol. In this specification, acylglycerol refers to a compound in which a hydroxyl group of glycerin is esterified with a fatty acid. The acylglycerol is not particularly limited and may be 1-monoacylglycerol, 2-monoacylglycerol, 1,2-diacylglycerol, 1,3-diacylglycerol, or triacylglycerol. Furthermore, the acylglycerol may be a monomer, a dimer, or a polymer of three or more. Acylglycerols of two or more mers can be obtained by thermal polymerization, oxidative polymerization, etc. Also, the acylglycerol may be a liquid or a solid at 25°C.

[0163] The method for confirming whether the rubber composition contains the acylglycerol is not particularly limited, 1 This can be confirmed by 1H-NMR measurement. For example, a rubber composition containing triacylglycerol is immersed in deuterated chloroform at 25°C for 24 hours, and after removing the rubber composition, it is measured at room temperature. 1 When 1H-NMR was measured and the tetramethylsilane (TMS) signal was set to 0.00 ppm, signals were observed around 5.26 ppm, 4.28 ppm, and 4.15 ppm. These signals are presumed to originate from hydrogen atoms bonded to carbon atoms adjacent to the oxygen atom of the ester group. In this paragraph, "around" refers to a range of ±0.10 ppm.

[0164] The aforementioned fatty acids are not particularly limited and may be either unsaturated or saturated fatty acids. Examples of unsaturated fatty acids include monounsaturated fatty acids such as oleic acid, and polyunsaturated fatty acids such as linoleic acid and linolenic acid. Examples of saturated fatty acids include butyric acid and lauric acid.

[0165] In particular, it is desirable that the fatty acid contains fatty acids with few double bonds, i.e., saturated fatty acids or monounsaturated fatty acids, and oleic acid is preferred. As a vegetable oil containing such fatty acids, for example, a vegetable oil containing saturated fatty acids or monounsaturated fatty acids may be used, or a vegetable oil that has been modified by transesterification or other means may be used. Furthermore, in order to produce a vegetable oil containing such fatty acids, plants may be improved by breeding, genetic modification, genome editing, etc.

[0166] As for vegetable oils, commercially available products from companies such as Idemitsu Kosan Co., Ltd., Sankyo Yuka Kogyo Co., Ltd., ENEOS Corporation, Orisoy Co., Ltd., H&R Co., Ltd., Toyokuni Oil Co., Ltd., Fuji Kosan Co., Ltd., and Nisshin Oillio Group Ltd. can be used.

[0167] Examples of animal oils include fish oil, beef tallow, whale oil, or oleyl alcohol derived from them.

[0168] When oil is included, the oil content per 100 parts by mass of rubber component is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and even more preferably 15 parts by mass or more, from the viewpoint of processability. Furthermore, 30 parts by mass or less is preferred, 25 parts by mass or less is more preferred, and 20 parts by mass or less is even more preferred. The oil content also includes the amount of oil contained in the oil-spread rubber.

[0169] Liquid Rubber The liquid rubber is not particularly limited as long as it is a polymer that is in a liquid state at 25°C, but examples include liquid butadiene rubber (liquid BR), liquid styrene butadiene rubber (liquid SBR), liquid isoprene rubber (liquid IR), liquid styrene isoprene rubber (liquid SIR), liquid farnesene rubber, etc. The liquid rubber may be used alone or in combination of two or more types.

[0170] When liquid rubber is included, its content per 100 parts by mass of rubber component is preferably 1 part by mass or more, more preferably 3 parts by mass or more, and even more preferably 5 parts by mass or more. Furthermore, the liquid rubber content is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and even more preferably 10 parts by mass or less. The liquid rubber content also includes the amount of stretchable liquid rubber used to stretch the rubber component.

[0171] Ester-based plasticizers Examples of ester-based plasticizers include dibutyl adipate (DBA), diisobutyl adipate (DIBA), dioctyl adipate (DOA), di-2-ethylhexyl azelaate (DOZ), dibutyl sebacate (DBS), diisononyl adipate (DINA), diethyl phthalate (DEP), dioctyl phthalate (DOP), diundecyl phthalate (DUP), dibutyl phthalate (DBP), dioctyl sebacate (DOS), tributyl phosphate (TBP), trioctyl phosphate (TOP), triethyl phosphate (TEP), trimethyl phosphate (TMP), thymidine triphosphate (TTP), tricresyl phosphate (TCP), and trixylenyl phosphate (TXP). Ester-based plasticizers may be used individually or in combination of two or more.

[0172] When an ester-based plasticizer is included, its content per 100 parts by mass of the rubber component is preferably 1 part by mass or more, more preferably 3 parts by mass or more, and even more preferably 5 parts by mass or more. The liquid rubber content is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and even more preferably 10 parts by mass or less. The ester-based plasticizer content also includes the amount of stretched ester-based plasticizer used to stretch the rubber component.

[0173] (Vulcanized rubber particles) Vulcanized rubber particles are particles made of vulcanized rubber, and specifically, rubber powder as specified in JIS K 6316:2017 can be used. From the viewpoint of environmental considerations and cost, recycled rubber powder produced from crushed waste tires is preferred. One type of vulcanized rubber particle may be used alone, or two or more types may be used in combination.

[0174] The vulcanized rubber particles are not particularly limited and may be either unmodified vulcanized rubber particles or modified vulcanized rubber particles.

[0175] Commercially available vulcanized rubber products can be used, such as those from Lehigh, Muraoka Rubber Industries, and others.

[0176] When vulcanized rubber particles are included, the content per 100 parts by mass of the rubber component can be appropriately adjusted, for example, within a range of more than 1 part by mass and less than 80 parts by mass.

[0177] (Processing aid) Examples of processing aids include fatty acid metal salts, fatty acid amides, amide esters, silica surfactants, fatty acid esters, mixtures of fatty acid metal salts and amide esters, and mixtures of fatty acid metal salts and fatty acid amides. For example, commercially available processing aids from companies such as Schill+Seilacher and Performance Additives can be used. Processing aids may be used individually or in combination of two or more.

[0178] When processing aids are included, the content per 100 parts by mass of rubber components is preferably 0.5 parts by mass or more, and more preferably 1 part by mass or more, from the viewpoint of exhibiting an effect of improving processability. Furthermore, from the viewpoint of wear resistance and fracture strength, it is preferably 10 parts by mass or less, more preferably 8 parts by mass or less, and even more preferably 5 parts by mass or less.

[0179] (wax) The wax is not particularly limited, and any wax commonly used in the tire industry can be suitably used, such as mineral waxes and plant-derived waxes. Mineral waxes refer to waxes derived from mineral resources such as oil and natural gas. Plant-derived waxes refer to waxes derived from natural resources such as plants. Among these, mineral waxes are preferred. Examples of plant-derived waxes include rice wax, carnauba wax, and candelilla wax. Examples of mineral waxes include paraffin wax, microcrystalline wax, and selected special waxes thereof, with paraffin wax being preferred. The wax according to this embodiment does not contain stearic acid. The wax can be commercially available from companies such as Ouchi Shinko Chemical Industry Co., Ltd., Nippon Seiro Co., Ltd., and Paramelt Co., Ltd. The wax may be used alone or in combination of two or more types.

[0180] When wax is included, the amount of wax per 100 parts by mass of rubber component is preferably 0.5 parts by mass or more, and more preferably 1 part by mass or more, from the viewpoint of weather resistance of the rubber. Furthermore, from the viewpoint of preventing whitening of the tire due to bloom, it is preferably 10 parts by mass or less, and more preferably 5 parts by mass or less.

[0181] (Stearic acid) When stearic acid is included, its content per 100 parts by mass of the rubber component is preferably 0.5 parts by mass or more, and more preferably 1 part by mass or more, from the viewpoint of processability. Furthermore, from the viewpoint of vulcanization rate, it is preferably 10 parts by mass or less, and more preferably 5 parts by mass or less.

[0182] (Zinc oxide) When zinc oxide is included, its content per 100 parts by mass of rubber component is preferably 0.5 parts by mass or more, more preferably 1.0 part by mass or more, and even more preferably 1.5 parts by mass or more, from the viewpoint of processability. Furthermore, from the viewpoint of wear resistance, it is preferably 5.0 parts by mass or less, more preferably 4.5 parts by mass or less, and even more preferably 4.0 parts by mass or less.

[0183] (Anti-aging agent) While not particularly limited, examples of anti-aging agents include naphthylamine-based anti-aging agents such as phenyl-α-naphthylamine; diphenylamine-based anti-aging agents such as octylated diphenylamine and 4,4'-bis(α,α'-dimethylbenzyl)diphenylamine; N-isopropyl-N'-phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD), N,N'-bis(1,4-dimethylpentyl)-p-phenylenediamine (77PD), N,N'-diphenyl-p-phenylenediamine (DPPD), and N,N'-ditril-p-phenylenediamine. Examples include p-phenylenediamine-based antioxidants such as methyl amine (DTPD), N-isopropyl-N'-phenyl-p-phenylenediamine (IPPD), and N,N'-di-2-naphthyl-p-phenylenediamine (DNPD); quinoline-based antioxidants such as polymers of 2,2,4-trimethyl-1,2-dihydroquinoline; monophenol-based antioxidants such as 2,6-di-t-butyl-4-methylphenol and styrenated phenol; and bis-, tris-, and polyphenol-based antioxidants such as tetrakis-[methylene-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate]methane. Among these, p-phenylenediamine-based antioxidants and quinoline-based antioxidants are preferred, and polymers of N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine and 2,2,4-trimethyl-1,2-dihydroquinoline are more preferred. Commercially available products include those from Seiko Chemical Co., Ltd., Sumitomo Chemical Co., Ltd., Ouchi Shinko Chemical Co., Ltd., Flexis, and others. The antioxidant may be used alone or in combination of two or more.

[0184] When an anti-aging agent is included, the content per 100 parts by mass of rubber component is preferably 0.5 parts by mass or more, and more preferably 1 part by mass or more, from the viewpoint of the rubber's resistance to ozone cracking. Furthermore, from the viewpoint of wear resistance and wet grip performance, it is preferably 10 parts by mass or less, and more preferably 5 parts by mass or less.

[0185] (Vulcanizing agent) Sulfur is preferably used as a vulcanizing agent. Suitable sulfurs include powdered sulfur, oil-treated sulfur, precipitated sulfur, colloidal sulfur, insoluble sulfur, and highly dispersible sulfur. The vulcanizing agent may be used alone or in combination of two or more types.

[0186] When sulfur is included as a vulcanizing agent, the amount of sulfur per 100 parts by mass of rubber component is preferably 0.1 parts by mass or more, more preferably 0.3 parts by mass or more, and even more preferably 0.5 parts by mass or more, from the viewpoint of ensuring a sufficient vulcanization reaction. Furthermore, from the viewpoint of preventing deterioration, it is preferably 5.0 parts by mass or less, more preferably 4.0 parts by mass or less, and even more preferably 3.0 parts by mass or less. When oil-containing sulfur is used as the vulcanizing agent, the amount of vulcanizing agent is the total amount of pure sulfur contained in the oil-containing sulfur.

[0187] Examples of vulcanizing agents other than sulfur include alkylphenol-sulfur chloride condensates, 1,6-hexamethylene-dithiosulfate sodium dihydrate, and 1,6-bis(N,N'-dibenzylthiocarbamoyldithio)hexane). These non-sulfur vulcanizing agents can be commercially available from companies such as Taoka Chemical Industries, Ltd., Lanxess Corporation, and Flexis. The vulcanizing agent may be used alone or in combination of two or more types.

[0188] (Vulcanization accelerator) Examples of vulcanization accelerators include sulfenamide, thiazole, thiuram, thiourea, guanidine, dithiocarbamate, aldehyde-amine or aldehyde-ammonia, imidazoline, or xanthate vulcanization accelerators. Among these, sulfenamide, thiazole, and guanidine vulcanization accelerators are preferred. The vulcanization accelerator may be used alone or in combination of two or more types.

[0189] Examples of sulfenamide-based vulcanization accelerators include N-tert-butyl-2-benzothiazolyl sulfenamide (TBBS), N-cyclohexyl-2-benzothiazolyl sulfenamide (CBS), and N,N-dicyclohexyl-2-benzothiazolyl sulfenamide (DCBS). Among these, N-cyclohexyl-2-benzothiazolyl sulfenamide (CBS) is preferred.

[0190] Examples of thiazole-based vulcanization accelerators include 2-mercaptobenzothiazole, cyclohexylamine salt of 2-mercaptobenzothiazole, and di-2-benzothiazolyl disulfide. Among these, 2-mercaptobenzothiazole is preferred.

[0191] Examples of guanidine-based vulcanization accelerators include 1,3-diphenylguanidine (DPG), 1,3-di-o-tolylguanidine, 1-o-tolylbiguanide, di-o-tolylguanidine salts of dicatecholborate, 1,3-di-o-cumenylguanidine, 1,3-di-o-biphenylguanidine, and 1,3-di-o-cumenyl-2-propionylguanidine. Among these, 1,3-diphenylguanidine (DPG) is preferred.

[0192] Examples of thiram-based vulcanization accelerators include tetrakis(2-ethylhexyl)thiram disulfide (TOT-N), tetramethylthiram disulfide (TMTD), tetraethylthiram disulfide, tetramethylthiram monosulfide (TMTM), dipentamethylenethiram disulfide, and dipentamethylenethiram tetrasulfide.

[0193] Examples of thiourea-based vulcanization accelerators include thiourea compounds such as thiacarbamide, diethylthiourea, dibutylthiourea, trimethylthiourea, and dioltotrilthiourea, as well as N,N'-diphenylthiourea, trimethylthiourea, and N,N'-diethylthiourea.

[0194] Examples of dithiocarbamate-based vulcanization accelerators include piperidinium pentamethylenedithiocarbamate (PPDC), zinc dimethyldithiocarbamate (ZnMDC), zinc diethyldithiocarbamate (ZnEDC), zinc dibutyldithiocarbamate (ZnBDC), zinc dibenzyldithiocarbamate (ZDBzC), zinc N-ethyl-N-phenyldithiocarbamate (ZnEPDC), zinc N-pentamethylenedithiocarbamate (ZnPDC), sodium dibutyldithiocarbamate (NaBDC), copper dimethyldithiocarbamate (CuMDC), iron dimethyldithiocarbamate (FeMDC), and tellurium diethyldithiocarbamate (TeEDC).

[0195] When a vulcanization accelerator is included, its content per 100 parts by mass of the rubber component is preferably 1 part by mass or more, and more preferably 1.5 parts by mass or more. Furthermore, the content of the vulcanization accelerator per 100 parts by mass of the rubber component is preferably 8 parts by mass or less, more preferably 7 parts by mass or less, and even more preferably 6 parts by mass or less. By keeping the content of the vulcanization accelerator within the above range, it tends to be possible to ensure fracture strength and elongation.

[0196] <Various materials containing carbon atoms> In this specification, various materials containing carbon atoms (e.g., rubber, oil, resin components, vulcanization accelerators, antioxidants, surfactants, etc.) may be derived from atmospheric carbon dioxide. Methods for obtaining these materials from carbon dioxide include directly converting carbon dioxide, or converting methane obtained through a methanation process in which methane is synthesized from carbon dioxide.

[0197] [Rubber composition for base treads] The components of the base tread rubber composition will now be described. Preferably, the base tread is at least one tire component made of a rubber composition containing recycled carbon black.

[0198] (Rubber component) The rubber composition contains a rubber component, preferably at least one of isoprene rubber (IR rubber), styrene-butadiene rubber (SBR), and butadiene rubber (BR). In this case, the rubber component may include rubber components other than isoprene rubber, SBR, and BR. In one embodiment, it is more preferable that the rubber component contains isoprene rubber and BR. In that case, other rubber components may be included in addition to isoprene rubber and BR, or it may consist only of isoprene rubber and BR. The rubber component is described below, as well as in the description of the rubber composition for clinch apex.

[0199] ≪Content≫ The content of isoprene-based rubber in 100% by mass of the rubber component is, for example, more than 30% by mass, preferably more than 35% by mass, more preferably 40% by mass or more, and even more preferably 50% by mass or more. On the other hand, the content is, for example, 100% by mass or less, preferably less than 90% by mass, and more preferably 80% by mass or less.

[0200] Furthermore, the BR content in 100% by mass of the rubber component is, for example, more than 5% by mass, preferably more than 10% by mass, more preferably more than 15% by mass, and even more preferably 20% by mass or more. On the other hand, the content is, for example, 60% by mass or less, preferably less than 55% by mass, more preferably less than 50% by mass, and even more preferably less than 45% by mass.

[0201] The total content of isoprene-based rubber and BR in 100% by mass of the rubber component is preferably more than 80% by mass, more preferably more than 90% by mass, and even more preferably more than 95% by mass, and may be 100% by mass.

[0202] (Filler) The filler may contain carbon black other than recycled carbon black (rCB) and silica. If the filler contains silica, it may further contain a silane coupling agent. The filler may further contain other fillers other than carbon black and silica. A description of each component that may constitute the filler is as described in the section on rubber compositions for clinch apex.

[0203] Total amount of carbon black B The total amount (parts by mass) of carbon black, including recycled carbon black, is preferably 25 parts by mass or more, more preferably 35 parts by mass or more, even more preferably 38 parts by mass or more, and even more preferably 40 parts by mass or more, per 100 parts by mass of rubber component. On the other hand, the total amount is preferably less than 85 parts by mass, more preferably less than 80 parts by mass, even more preferably less than 75 parts by mass, and even more preferably 70 parts by mass or less. When the total amount of carbon black is within the above range, sufficient reinforcing properties, good dispersion in the rubber, and sufficient rubber strength and durability tend to be obtained.

[0204] Furthermore, the same explanation given for the rubber composition for clinch apex can be applied to carbon black (including recycled carbon black).

[0205] (Other compounding agents) For any other information, the explanation provided for the rubber composition for clinch apex can be applied similarly.

[0206] [Rubber composition for inner liner rubber] The components of the rubber composition for the inner liner rubber will now be described. Preferably, the inner liner is at least one tire component made of a rubber composition containing recycled carbon black.

[0207] (Rubber component) The rubber component may consist solely of butyl rubber, or it may contain rubber components other than butyl rubber. The rubber components are described below, as well as in the description of the rubber composition for clinch apex.

[0208] ≪Butyl rubber≫ As butyl rubbers, polymers and derivatives containing isobutylene units and isoprene units as repeating units are preferred. Examples of such butyl rubbers include butyl rubber (IIR), brominated butyl rubber (Br-IIR), chlorinated butyl rubber (Cl-IIR), and other halogenated butyl rubbers. Among these, halogenated butyl rubber is preferred because it can improve sheet processability and air barrier properties in a balanced way, and brominated butyl rubber and chlorinated butyl rubber are more preferred. One or more of these can be used.

[0209] In addition to regular butyl rubber (butyl rubber other than recycled butyl rubber), recycled butyl rubber can also be used in combination with other butyl rubbers. Since recycled butyl rubber usually has a high content of unhalogenated butyl rubber (regular butyl rubber), using it in combination with halogenated butyl rubber ensures good air barrier properties and vulcanization speed. Recycled butyl rubber may be used alone or in combination of two or more types.

[0210] When the rubber component includes rubber components other than butyl rubber, examples of other rubber components include diene rubbers such as isoprene rubber (IR rubber), butadiene rubber (BR), styrene-butadiene rubber (SBR), styrene-isoprene-butadiene rubber (SIBR), chloroprene rubber (CR), and acrylonitrile-butadiene rubber (NBR). The explanation given for the rubber composition for clinch apex rubber can be applied similarly to these other rubber components. These other rubber components may be used individually or in combination of two or more.

[0211] ≪Content≫ From the viewpoint of sufficient air barrier properties, the content of butyl rubber in 100% by mass of the rubber component is preferably more than 70% by mass, more preferably more than 75% by mass, even more preferably more than 80% by mass, and even more preferably 100% by mass.

[0212] (Filler) The filler may contain carbon black other than recycled carbon black (rCB) and silica. If the filler contains silica, it may further contain a silane coupling agent. The filler may further contain other fillers other than carbon black and silica. A description of each component that may constitute the filler is as described in the section on rubber compositions for clinch apex.

[0213] Total amount of carbon black B The total amount (parts by mass) of carbon black, including recycled carbon black, is preferably 25 parts by mass or more, more preferably 35 parts by mass or more, even more preferably 40 parts by mass or more, and still more preferably 45 parts by mass or more, per 100 parts by mass of rubber component. On the other hand, the total amount is also preferably less than 85 parts by mass, more preferably less than 80 parts by mass, even more preferably less than 75 parts by mass, and still more preferably 70 parts by mass or less. When the total amount of carbon black is within the above range, sufficient reinforcing properties, good dispersion in the rubber, and sufficient rubber strength and durability tend to be obtained.

[0214] Furthermore, the same explanation given for the rubber composition for clinch apex can be applied to carbon black (including recycled carbon black).

[0215] (Other compounding agents) For any other information, the explanation provided for the rubber composition for clinch apex can be applied similarly.

[0216] [Rubber composition for sidewalls] The components of the rubber composition for the sidewall will now be described. Preferably, at least one tire component made of a rubber composition containing recycled carbon black is the sidewall.

[0217] (Rubber component) The rubber composition contains a rubber component, preferably at least one of isoprene rubber (IR rubber), styrene-butadiene rubber (SBR), and butadiene rubber (BR). In this case, the rubber component may include rubber components other than isoprene rubber, SBR, and BR. In one embodiment, it is more preferable that the rubber component contains isoprene rubber and BR. In that case, other rubber components may be included in addition to isoprene rubber and BR, or it may consist only of isoprene rubber and BR. The rubber component is described below, as well as in the description of the rubber composition for clinch apex.

[0218] ≪Content≫ The explanation regarding the content of rubber components is as described in the section on rubber compositions for clinch apex, but the content of isoprene-based rubber in 100% by mass of rubber components is, for example, more than 10% by mass, preferably more than 15% by mass, more preferably more than 20% by mass, even more preferably 30% by mass or more, and even more preferably 40% by mass or more. On the other hand, the content is, for example, 80% by mass or less, preferably less than 70% by mass, and even more preferably less than 60% by mass.

[0219] Furthermore, the BR content in 100% by mass of the rubber component is, for example, more than 10% by mass, preferably 20% by mass or more, and more preferably more than 30% by mass. On the other hand, the content is, for example, less than 90% by mass, preferably less than 80% by mass, more preferably less than 75% by mass, even more preferably less than 70% by mass, and even more preferably 60% by mass or less.

[0220] Furthermore, the total content of isoprene-based rubber and BR in 100% by mass of the rubber component is preferably more than 80% by mass, more preferably more than 90% by mass, and even more preferably more than 95% by mass, and may be 100% by mass.

[0221] (Filler) The filler may contain carbon black other than recycled carbon black (rCB) and silica. If the filler contains silica, it may further contain a silane coupling agent. The filler may further contain other fillers other than carbon black and silica. The descriptions of each component that may make up the filler are as described in the section on rubber compositions for clinch apex, except for the descriptions below.

[0222] Total amount of carbon black B The total amount (parts by mass) of carbon black, including recycled carbon black, is preferably 25 parts by mass or more, more preferably 35 parts by mass or more, even more preferably 40 parts by mass or more, and even more preferably 50 parts by mass or more, per 100 parts by mass of rubber component. On the other hand, the total amount is also preferably less than 85 parts by mass, more preferably less than 80 parts by mass, even more preferably less than 75 parts by mass, and even more preferably 70 parts by mass or less. When the total amount of carbon black is within the above range, sufficient reinforcing properties, good dispersion in the rubber, and sufficient rubber strength and durability tend to be obtained.

[0223] Furthermore, the same explanation given for the rubber composition for clinch apex can be applied to carbon black (including recycled carbon black).

[0224] (Other compounding agents) For any other information, the explanation provided for the rubber composition for clinch apex can be applied similarly.

[0225] [Insulation rubber composition] Preferably, at least one tire component made of a rubber composition containing recycled carbon black is an insulation. The explanations regarding the rubber components used in the insulation rubber composition and their content, the components that can constitute the filler and their content, and other compounding agents and their content can be applied to the explanations given for each tire component rubber composition above. It is also preferable to apply the explanation given for the clinch apex rubber composition in the same way.

[0226] <Other tire components> In this specification, a tire may include other tire components not described above. Such other tire components are not particularly limited and may include a variety of those commonly used in tires. They may also be used as cord-topping rubber covering the cords.

[0227] In this specification, various materials containing carbon atoms (e.g., rubber, oil, resin components, vulcanization accelerators, antioxidants, surfactants, etc.) may be derived from atmospheric carbon dioxide. As a method for obtaining the formulations of the present invention from carbon dioxide, carbon dioxide may be directly converted, or methane obtained through a methanation process in which methane is synthesized from carbon dioxide may be converted.

[0228] [Manufacturing method] Rubber compositions can be manufactured by known methods. For example, they can be manufactured by mixing each of the above components using rubber mixing equipment such as an open roll or closed-type kneader (Banbury mixer, kneader, etc.).

[0229] The mixing process includes, for example, a base mixing process in which compounding agents and additives other than the vulcanizing agent and vulcanization accelerator are mixed, and a final mixing (F mixing) process in which the vulcanizing agent and vulcanization accelerator are added to the mixture obtained in the base mixing process and mixed. Furthermore, the base mixing process can be divided into multiple processes as desired.

[0230] While there are no particular limitations on the mixing conditions, one example is to mix the base mixture at a discharge temperature of 150-170°C for 3-10 minutes, and then mix the final mixture at 70-110°C for 1-5 minutes.

[0231] The tire according to this embodiment can be manufactured by conventional methods using the rubber composition. Specifically, the rubber composition in an unvulcanized state is extruded in an extruder equipped with a die of a predetermined shape to match the shape of a desired tire component, and then bonded together with other tire components on a tire molding machine while adjusting to form a predetermined tire structure, thereby forming an unvulcanized tire by conventional methods. This unvulcanized tire is then heated and pressurized in a vulcanizing machine to manufacture the tire. The vulcanization conditions are not particularly limited, and for example, a method of vulcanizing at 140 to 170°C for 10 to 40 minutes can be used.

[0232] [Application] In this specification, tires, whether pneumatic or non-pneumatic, can be used for any purpose, including passenger car tires, large passenger car tires, large SUV tires, racing tires, motorcycle tires, heavy-duty tires, and run-flat tires. Passenger car tires are defined as tires intended for use on four-wheeled vehicles with a maximum load capacity of less than 1400 kg. Heavy-duty tires are defined as tires with a maximum load capacity of 1400 kg or more. In this specification, tires can be used as all-season tires, summer tires, and winter tires such as studless tires. [Examples]

[0233] The following examples (case studies) are shown as preferred for implementation, but the scope of the present invention is not limited to these examples. Each rubber composition for tire components and a tire having a tire structure obtained using the various chemicals shown below were examined according to each table, and the results calculated based on the evaluation method described below are shown at the bottom of each table.

[0234] [Various medicines] The various chemicals used in the examples and comparative examples are summarized below. Natural rubber: TSR20 BR: UBEPOL BR150B manufactured by UBE Industries, Ltd. (unmodified BR, cis content: 97 mol%, Mw: 440,000) Butyl rubber: Bromobutyl rubber 2255 manufactured by ExxonMobil Carbon black 1 (CB1): Cabot Japan, Ltd.'s Show Black N550 (N2SA: 42 m 2 / g, ash content: 1.0 mass% or less) Carbon black 2 (CB2): Cabot Japan, Ltd.'s Show Black N330 (N2SA: 75 m 2 / g, ash content: 1.0 mass% or less) Carbon black 3 (CB3): Cabot Japan, Ltd.'s Show Black N660 (N2SA: 35 m 2 / g, ash content: 1.0 mass% or less) Recycled carbon black (rCB): Carbon black obtained from the thermal decomposition process of tires (ash content: 17 mass%) Oil: Diana Process NH-70S (aromatic process oil) manufactured by Idemitsu Kosan Co., Ltd. Wax: Oz Ace 03P55 (paraffin wax) manufactured by Nippon Seiro Co., Ltd. Antioxidant: Nocrack 6C (N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine) manufactured by Ouchi Shinko Chemical Industry Co., Ltd. Stearic acid: Tsubaki Bead Stearic Acid manufactured by NOF Corporation Zinc oxide: Zinc white No. 2 manufactured by Mitsui Mining & Smelting Co., Ltd. Sulfur: HK-200-5 (5% oil-containing powdered sulfur) manufactured by Hosoi Chemical Industry Co., Ltd. Vulcanization accelerator: Noxeller CZ (N-cyclohexyl-2-benzothiazolylsulfenamide (CBS)) manufactured by Ouchi Shinko Chemical Industry Co., Ltd.<- Band cord 1: Polyethylene terephthalate fiber, diameter 0.8 mm, cord structure 2200 dtex / 2 Band cord 2: Polyethylene terephthalate fiber, diameter 1.1 mm, cord structure 3300 dtex / 2 Band cord 3: Polyethylene terephthalate fiber, diameter 0.5 mm, cord structure 1100 dtex / 2 Band cord 4: Polyethylene terephthalate fiber, diameter 0.4 mm, cord composition 1670 dtex / 1 Bandcode 5: Polyethylene terephthalate fiber, 1.0 mm diameter, code structure 1670 dtex / 3 Bandcode 6: Polyethylene terephthalate fiber, 0.6 mm diameter, code structure 1440 dtex / 2

[0235] [Examples and Comparative Examples] <Tires using rubber composition for clinch apex> According to the formulation shown in Table 1, the chemicals other than sulfur and vulcanization accelerator are mixed in a 1.7 L closed Banbury mixer for 5 minutes until the discharge temperature reaches 170°C to obtain a mixture. Next, sulfur and vulcanization accelerator are added to the mixture using a twin-screw open roll and mixed for 4 minutes until the temperature reaches 105°C to obtain an unvulcanized rubber composition. The unvulcanized rubber composition is extruded into the shape of a clinch apex using an extruder equipped with a die of a predetermined shape, and bonded together with other tire components to form an unvulcanized tire. Each test tire is manufactured by press vulcanization at 170°C for 12 minutes (tire size: 195 / 65R15, tire weight G: 7.8 kg, maximum load capacity W). L : 615kg, G / W L :0.0127). The band consists of a single band ply with band cords having the diameter shown in the table, arranged in a pattern of 50 / 50mm or 70 / 50mm.

[0236] <Tires using rubber compositions for base treads> According to the formulation shown in Table 2, all chemicals except sulfur and vulcanization accelerator are mixed in a 1.7L sealed Banbury mixer at a discharge temperature of 150°C for 5 minutes. Next, sulfur and vulcanization accelerator are added to the resulting mixture and kneaded in an open roll for 4 minutes until it reaches 105°C to obtain an unvulcanized rubber composition for the inner liner. The unvulcanized rubber composition for the base tread is molded into the shape of the base tread and bonded together with other tire components to form an unvulcanized tire. Each test tire is manufactured by press vulcanization at 170°C for 12 minutes (tire size: 195 / 65R15, tire weight G: 7.8kg, maximum load capacity W). L : 615kg, G / W L :0.0127). The band consists of a single band ply with band cords having the diameter shown in the table, arranged in a pattern of 50 / 50mm or 40 / 50mm.

[0237] <Tires using rubber compositions for inner liners> According to the formulation shown in Table 3, the chemicals other than sulfur and vulcanization accelerator are mixed in a 1.7 L sealed Banbury mixer for 4 minutes until the discharge temperature reaches 160°C to obtain a mixture. Next, using a twin-screw open roll mixer, sulfur and vulcanization accelerator are added to the obtained mixture and mixed for 4 minutes until the temperature reaches 80°C to obtain an unvulcanized rubber composition. The unvulcanized rubber composition for the inner liner is molded into a sheet shape and bonded together with other tire components to form an unvulcanized tire, which is then press-vulcanized for 12 minutes under conditions of 170°C to produce each test tire (tire size: 195 / 65R15, tire weight G: 7.8 kg, maximum load capacity W L : 615kg, G / W L :0.0127). The band consists of a single band ply with band cords having the diameters shown in the table, arranged in a pattern of 50 / 50mm, 40 / 50mm, or 35 / 50mm.

[0238] <Tires using rubber composition for sidewalls> According to the formulation shown in Table 4, the chemicals other than sulfur and vulcanization accelerator are mixed in a 1.7 L sealed Banbury mixer for 5 minutes until the discharge temperature reaches 170°C to obtain a mixture. Next, sulfur and vulcanization accelerator are added to the mixture using a twin-screw open roll mixer and mixed for 4 minutes until the temperature reaches 105°C to obtain an unvulcanized rubber composition. The unvulcanized rubber composition for the sidewall is extruded into the shape of the sidewall using an extruder equipped with a die of a predetermined shape, and bonded together with other tire components to form an unvulcanized tire. Each test tire is manufactured by press vulcanization at 170°C for 12 minutes (tire size: 195 / 65R15, tire weight G: 7.8 kg, maximum load capacity W). L : 615kg, G / W L :0.0127). The band consists of a single band ply with band cords having the diameter shown in the table, arranged in a pattern of 50 / 50mm or 70 / 50mm.

[0239] [evaluation] For each test tire, the results measured using the following method are recorded in the corresponding column of the table below. Unless otherwise specified, each test tire is used after being brought to its normal state.

[0240] <Durability> Each test tire, inflated with 230 kPa of air, is mounted on a drum-type running test machine. A longitudinal load of 18.75 kN is applied to the tire, and it is driven on the drum at a speed of 80 km / h. The distance traveled until the tire breaks is measured. The results are expressed as an index, with the reference comparison set to 100. A higher index indicates superior durability.

[0241] [Table 1]

[0242] [Table 2]

[0243] [Table 3]

[0244] [Table 4]

[0245] [Embodiment] Examples of embodiments of the present invention are shown below.

[0246] [1] A tire comprising a band and a tire member composed of a rubber composition containing recycled carbon black, wherein the band includes at least one band ply in which a plurality of band cords made of polyethylene terephthalate fibers are arranged, where A is the thickness (mm) of the tire member, where B is the total amount (parts by mass) of carbon black including recycled carbon black in the rubber composition with respect to 100 parts by mass of the rubber component in the rubber composition, where C is the number of driven-in band cords per 50 mm of the band ply width in a cross-section orthogonal to the longitudinal direction of the band cord (number / ​50 mm), when the diameter (mm) of the band cord is D, a tire in which A to D satisfy the following formula (1), and the value of D × C / (B × A) is preferably more than 0.13 and less than 0.58. (1) 0.07 < D × C / (B × A) < 0.60 [2] The formula (1) is 0.16 < D × C / (B × A) < 0.55 and the value of D × C / (B × A) is preferably more than 0.18 and less than 0.55, more preferably more than 0.20 and less than 0.52, the tire according to [1]. [3] The number of driven-in band cords is 40 or more and 80 or less, preferably 45 or more and 75 or less per 50 mm of the ply width of the band ply, the tire according to [1] or [2]. [4] The tire according to any one of [1] to [3], wherein the diameter of the band cord is less than 1.2 mm, preferably less than 1.0 mm, more preferably less than 0.9 mm, and even more preferably 0.8 mm or less. [5] The tire according to any one of [1] to [4], wherein the total amount B of carbon black is 25 parts by mass or more, preferably 35 parts by mass or more, more preferably 40 parts by mass or more, and even more preferably 50 parts by mass or more, per 100 parts by mass of rubber component. [6] The tire according to any one of [1] to [5], wherein the fineness of the band cord is 1000 dtex or more, preferably 1500 dtex or more, and more preferably 2000 dtex or more. [7] The tire according to any one of [1] to [6], wherein the tire component is at least one selected from the clinch apex, base tread, inner liner, sidewall, and insulation. [8] The tire according to any one of [1] to [7], wherein the tire member is at least one selected from the clinch apex, base tread, and sidewall, and the rubber composition comprises 40% to 80% by mass, preferably 40% to 75% by mass, of isoprene-based rubber in 100% by mass of the rubber component. [9] The tire according to any one of [1] to [8], wherein the tire member is at least one selected from a clinch apex, a base tread, and a sidewall, and the rubber composition comprises 20% to 60% by mass, preferably 25% to 60% by mass, of butadiene rubber in 100% by mass of the rubber component.

[10] The tire according to any one of [1] to [7], wherein the tire member is an inner liner, and the rubber composition contains more than 80% by mass, preferably 100% by mass, of butyl rubber in 100% by mass of the rubber components.

[11] The tire according to any one of [1] to

[10] , wherein the band cords are arranged such that the number of band cords driven into the outer region of the band is greater than the number of band cords driven into the central region of the band.

[12] The tire according to any one of [1] to

[11] , wherein the band cords are arranged such that the rigidity of the band cords located in the outer region of the band is higher than that of the band cords located in the central region of the band.

[13] Maximum load capacity of the tire W L Ratio of tire weight G (kg) to (kg) (G / W L A tire according to any one of [1] to

[12] , wherein the ratio is 0.0135 or less, preferably 0.0130 or less, and more preferably 0.0128 or less.

[14] The tire according to any one of [1] to

[13] , wherein the band cord is made of recycled polyethylene terephthalate fiber. [Explanation of symbols]

[0247] 1 tire 2. Clinch Apex 3 Sidewall 4. Inner Liner 5 Base Tread 6 bands 7 Insulation CL Tire centerline (equator) T2 Clinch Apex Thickness T3 sidewall thickness T4 Inner Liner Thickness T5 Base tread thickness T7 Insulation Thickness

Claims

1. A tire comprising a band and a tire member made of a rubber composition containing recycled carbon black, The band includes at least one band ply in which a plurality of band cords made of polyethylene terephthalate fibers are arranged, Let A be the thickness (mm) of the tire member. Let B be the total amount (parts by mass) of carbon black, including recycled carbon black, in the rubber composition relative to 100 parts by mass of the rubber component in the rubber composition. Let C be the number of band cords inserted per 50 mm of band ply width in a cross section perpendicular to the longitudinal direction of the band cord. When the diameter (mm) of the aforementioned band cord is D, Tires A through D satisfy the following equation (1). (1) 0.07 < D × C / (B × A) < 0.60

2. Equation (1) is, 0.16 < D × C / (B × A) < 0.55 The tire according to claim 1.

3. The tire according to claim 1 or 2, wherein the number of band cords driven in is 40 or more and 80 or less per 50 mm ply width of the band ply.

4. The tire according to claim 1 or 2, wherein the diameter of the band cord is less than 1.2 mm.

5. The tire according to claim 1 or 2, wherein the total amount B of the carbon black is 25 parts by mass or more per 100 parts by mass of the rubber component.

6. The tire according to claim 1 or 2, wherein the fineness of the band cord is 1000 dtex or more.

7. The tire according to claim 1 or 2, wherein the tire component is at least one selected from the clinch apex, base tread, inner liner, sidewall, and insulation.

8. The tire according to claim 1 or 2, wherein the tire member is at least one selected from a clinch apex, a base tread, and a sidewall, and the rubber composition contains 40% to 80% by mass of isoprene-based rubber in 100% by mass of the rubber component.

9. The tire according to claim 1 or 2, wherein the tire member is at least one selected from a clinch apex, a base tread, and a sidewall, and the rubber composition contains 20% to 60% by mass of butadiene rubber in 100% by mass of the rubber component.

10. The tire according to claim 1 or 2, wherein the tire member is an inner liner, and the rubber composition contains more than 80% by mass of butyl rubber in 100% by mass of the rubber component.

11. The tire according to claim 1 or 2, wherein the number of band cords driven into the outer region of the band is greater than the number of band cords driven into the central region of the band.

12. The tire according to claim 1 or 2, wherein the band cords are arranged such that the rigidity of the band cords arranged in the outer region of the band is higher than that of the band cords arranged in the central region of the band.

13. The maximum load capacity of the tire W L Ratio of tire weight G (kg) to (kg) (G / W) L The tire according to claim 1 or 2, wherein the coefficient of gravity is 0.0135 or less.

14. The tire according to claim 1 or 2, wherein the band cord is made of recycled polyethylene terephthalate fibers.

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